<template>
  <div class="star" :class="starType">
    <span
      v-for="(itemClass,index) in itemClasses"
      :class="itemClass"
      class="star-item"
      :key="index"
    >
    </span>
  </div>
</template>

<script>
const LENGTH = 5
const CLS_ON = 'on'
const CLS_HALF = 'half'
const CLS_OFF = 'off'

export default {
  name: 'star',
  props: {
    size: Number,
    score: Number
  },
  computed: {
    starType () {
      return 'star-' + this.size
    },
    itemClasses () {
      let result = []
      let score = Math.floor(this.score * 2) / 2
      let hasDecimal = score & 1 !== 0
      let integer = Math.floor(score)
      for (let i = 0; i < integer; i++) {
        result.push(CLS_ON)
      }
      if (hasDecimal) {
        result.push(CLS_HALF)
      }
      while (result.length < LENGTH) {
        result.push(CLS_OFF)
      }
      return result
    }
  }
}
</script>

<style lang="stylus" scoped>
  @import "../../common/stylus/mixin.styl"
  .star
    font-size 0
    .star-item
      display inline-block
      background-repeat no-repeat
    &.star-48
      .star-item
        width .4rem
        height .4rem
        margin-right .44rem
        background-size .4rem .4rem
        &:last-child
          margin-right 0
        &.on
          bg-image('star48_on')
        &.half
          bg-image('star48_half')
        &.off
          bg-image('star48_off')
    &.star-36
      .star-item
        width .3rem
        height .3rem
        margin-right .12rem
        background-size .3rem .3rem
        &:last-child
          margin-right 0
        &.on
          bg-image('star36_on')
        &.half
          bg-image('star36_half')
        &.off
          bg-image('star36_off')
    &.star-24
      .star-item
        width .2rem
        height .2rem
        margin-right .06rem
        background-size .2rem .2rem
        &:last-child
          margin-right 0
        &.on
          bg-image('star24_on')
        &.half
          bg-image('star24_half')
        &.off
          bg-image('star24_off')
</style>
